Case 208. Babesiosis (47 y-o M)
    Peripheral blood smear in an Awaji resident who had a recent history of blood transfusion for gastrectomy    
Key words : Babesia microti, crusiform body
Large-sized ring form parasites are seen in many red cells. Multiple infection in one red cell is common. Babesia microti does not produce pigment. Usually, the disease is transmitted by bite of Ixodes tick.   Babesia microti in rat blood (Giemsa)
The diagnostic hallmark of babesiosis (piroplasmosis) is the cruciform body (tetrad) forming a malthese cross-like structure. This is a zoonotic disorder.Splenectomized patients are at high risk of babesiosis. The infection is endemic in Connecticut and on the islands off of Massachusetts and New York. B. bovis infection in human has been reported in Europe.
Babesia gibsoni in dog blood (Giemsa)
The size of the ring form of B. gibsoni is much smaller than B. microti. Primary infection of B. gibsoni may be fatal to the dog, because of acute hemolysis. Babesiosis is an important protozoan disorder among domestic and wild animals, including the horse, cow, deer, rat and dog.